We are given a red flower plant. This means its homozygous dominant (RR). We are given a white flower plant. This means it is homozygous recessive (rr). Each plant will give its allele. The red one will always give R and the white one will always give r. Heterozygous (Rr) plants have pink flowers. So they will all be pink.
The main reason that attitudes are more often revealed in spoken rather than written language is because in writing, we can easily conceal our attitudes. The correct answer is D.