The varieties of corn can be improved by which of the following methods?

Show the answer and explanation

Answer: (c) Double cross

Double-cross hybrids (crossing two single-cross hybrids) made the first high-yielding hybrid maize.

Why the others are wrong

(a) A dihybrid cross is a genetics experiment, not a breeding method.

(b) Back-crossing adds a trait to an existing variety.

(d) Natural selection is not a breeding technique.

None.

🔒 Hybrid maize: single-cross (now common) and double-cross (historic).