Let's just go through all possible answers and see which ones give what you are asking for.
1
the Total number of marbles is 10
You have 2 blue marbles
P(blue) = 2/10 = 1/5 which is not a good answer.
2
There are 3 red marbles.
P(red) = 3/10 = 0.3 which is greater than 1/5 <<<< Possible answer.
3
3 red marbles out of 10 = 3/10
2 blue marbles = 2/9
Probability of (red then blue)= 3/10 * 2/9 = 1/15 which is not greater than 1/5
4
1 white marble replacing it and white again.
1/2 * 1/2 = 1/4 which is greater than 1/5 <<<<<<<< Answer
5
There are 5 white marbles. 5/10 is the probability of drawing a white. P(white) = 1/2. That is greater than 1/5.<<<< Possible Answer
Answers 2,4,5