Question 3
A pure tall pea plant is crossed with a pure dwarf one. What is the F1 generation like?
The right answer is the one marked above.
Every plant is tall. Not one F1 plant is dwarf, and none is intermediate. Tallness is the dominant form, so it shows whenever it is present.
The 3 : 1 ratio is the F2, one generation later. Reading the question carefully to see which generation is meant is half the work in this topic.