In Garden Peas, the Allele for Tall Plants Is Dominant

Multiple Choice

In garden peas, the allele for tall plants is dominant over the allele for short plants. Imagine that a true-breeding tall plant is crossed with a short plant. Then one of their offspring is test crossed. Out of 20 offspring resulting from the test cross, about how many should be tall?

A) 0
B) 10
C) 15
D) 20
E) 5