Answer:
Option D
Step-by-step explanation:
There are two different traits represented by the term "SsTt". Where "S" is the allele for a dominant trait 1 and "s" is the allele for a recessive trait 1. Like wise "T" is the allele for a dominant trait 2 and "t" is the allele for recessive trait 2.
In a genetic combination , both the allels of both the traits will pair up with each other one by one.
i.e "T" will pair up with both "S" and "s" to form "TS" and "Ts" gametes
Similarly "t"will pair up with both "S" and "s" to form "tS" and "ts" gametes
Hence, option D is correct