The most important contribution of agriculture to mankind is the provision of

A. shelter

B. employment

C. foreign exchange

D. food

An advantage of commercial agriculture is that it

A. requires small space

B. requires skilled labour

C. produces high returns

D. involves low capital

Which of the following statements about communal land tenure system is true?

A. it gives the owner complete freedom on the land

B. the land can be used as collateral for agricultural loans

C. the land can be shared by the owner's children

D. mechanical agriculture can be profitably practised

Agricultural land use is negatively affected by

A. type of soil

B. climatic factors

C. increase in population

D. increase in soil micro-organisms

The practice of growth both food and forage crops simultaneously on the same piece of land is called

A. pastoral farming

B. ley farming

C. crop rotation

D. continuous cropping

The use of land for agricultural purpose involves the following except

A. livestock grazing

B. fish farming

C. road construction

D. crop production

The natural grasslands of West Africa are generally located in the

A. rain forest

B. guinea savanna

C. mangroves

D. equatorial belts

The following processes in soil formation are caused by biotic factors except

A. bacterial decomposition of plants

B. soil mixing and turning by earthworms

C. burrowing of rodents

D. soil disintegration by dehydration

Which of the following rocks is not formed from pre-existing rocks?

A. limestone

B. granite

C. shale

D. marble

Chemical weathering is fastest in

A. cool weather

B. hot weather

C. high altitudes

D. low altitudes

It is not advisable to apply fresh farmyard manure because

A. its heat of decomposition may cause scorching of plants

B. some microorganisms in the manure may die

C. the manure may increase soil acidity

D. the manure may increase soil alkalinity

Magnesium deficiency in crops can be corrected by the application of

A. dolomite

B. limestone

C. quicklime

D. urea