Drawing a punnet square on a seperate peice of paper (which I did) we have the traits as follows:
YY
Yy
Yy
yy
So as seeing 1 of 4 is defenitly a Red (yy) 2 of the flowers are 50/50 being red or yellow. I'm not really sure which answer is correct but I would choose answer 3 as there are 3 flowers with the chance of being red.
HOPE THIS HELPED!!