1. A cross between a tall plant (TT) and a short pea plant (tt) resulted in progeny that was all tall plants because (a) tallness is the dominant trait (b) shortness is the dominant trait (c) tallness is the recessive trait (d) height of the pea plant is not governed by gene ‘T’ or ‘t’

The answer is (a) tallness is the dominant trait

Explanation:

A cross between a tall plant (TT) and a short pea plant (tt) results in the progeny that is all tall plants but with Tt genotype. In the heterozygous plants the dominant trait is expressed phenotypically. Single copy of the ‘T’ is enough to make the plant tall.