What claim is made about plant species found in Kazakhstan?

a) Approximately 157 species of cultivated temperate fruits originated in Kazakhstan.

b) Ninety percent of all domesticated crops are either direct precursors or close wild relatives of plant species found in Kazakhstan.

c) Of the plant species found in Kazakhstan, ninety percent are species of apples.

d) Aside from apples, at least 157 plant species found in Kazakhstan are either direct precursors or close wild relatives of domesticated crops.