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A government campaign was conducted in an agricultural area where sparrow population was exterminated as these birds were known to eat grains and decrease crop yield. However, in the months that followed, grain production was severely reduced leading to famines in that area.

The given graph traces the population changes of one more species in that area after campaign.
Which of the following best explains this?

AThere was overgrowth of crops due to reduced sparrow population causing the crops to compete for available resources thereby leading to crop failure.
BThe crash in sparrow population caused the population of locusts (which sparrows prey upon) to spike, which in turn wiped out available crops in field.
CThe increase in the population of locust is not related with the decrease in the population of sparrow.
DNone of these

What should Seema do to find out whether a material is a magnet?

AFind out if the material is a metal or a non-metal.
BFind out if the material is a conductor or an insulator.
CFind out if the material can be attracted to a steel plate.
DFind out if the material can be repelled by a compass.

Refer to the given flow chart and select the INCORRECT option regarding X, Y and Z.


AX can be mould while Z can be Pistia.
BY can be elm while Z can be Hydrilla.
CZ can be cactus while Y can be duckweed.
DBoth A and B

Three identical lamps are connected to a battery as shown in the diagram. Each lamp operates at normal brightness and the ammeter (of negligible resistance) registers a steady current.

The filament of the lamp W breaks. What will happen to the ammeter reading and to the brightness of the remaining lamps?
Ammeter reading-----Lamp brightness

AIncreases---Decreases
BDecreases---Remains unchanged
CRemains unchanged---Remains unchanged
DBecomes zero---Becomes zero

Refer to the given flow chart.

Select the correct option regarding P - S.

AQ could be Dahlia and sweet potato whereas S could be turmeric and ginger.
BP could be maize whereas R could be Bryophyllum.
CQ could be carrot whereas R could be Eichhornia.
DP could be papaya whereas S could be onion.

Refer to the given flow chart and select the incorrect statement regarding W, X, Y and Z.


AW could be synthetic fibre whereas Z could be cellulosic fibre.
BX could be protein fibre which is obtained by shearing the animal.
CY could be flax fibre which is obtained from the fruit of kapok tree.
DRetting can be involved in processing of obtaining Z.

Read the given paragraph and select the correct option to fill in the blanks.
__(i)__ is the most abundant fossil fuel found on Earth. Lignite is one of its types. In India, mines of (i) are situated in __(ii)__ .

A person riding a bicycle observes a passenger sitting in the bus. He finds that the passenger closed his glass window displacing 25 cm in forward direction with a constant speed in 1 sec. Bus overtakes the cyclist in 2 sec. Initially the person was at the middle of the bus as shown in the given figure. Length of the bus is 20 m. If, both the person and bus are moving with constant speed in the same direction, then velocity of the glass window with respect to the person was


A0.25 m/s
B2.5 m/s
C5.25 m/s
D3 m/s

Refer to the given flow chart showing flow of energy in a food chain.

Select the incorrect statements regarding L, M, N and O.
(i) O helps in cleaning of environment as well as recycling of nutrients.
(ii) The role of M comes when plants and animals die.
(iii) L operates at all levels of food chain.
(iv) N eats other animals and gets its food indirectly from L.

A(i) and (iv) only
B(i), (iii) and (iv) only
C(ii) and (iii) only
D(i), (ii), (iii) and (iv)

Select the incorrect match.

ACatalytic converter – Reduces vehicular exhaust
BElectrostatic precipitator – Reduces release of pollutant gases from factories
CMontreal Protocol – Focuses on reducing the levels of CFCs
DNone of these