Answer:
B) 1:3
Explanation:
Let's layout the information given firstly.
Marigolds= 18
Petunias= 6
In ratios, you need to follow the arrangement, for say in this question they say petunias go first, so the ratio should involve the value 6 first.
Therefore, it will give you, 6:18.
Now, you need to simplify this ratio. Just simplify it as it were, a fraction. Divide each number by a common factor, in this case, it is 6. Once you've done that, you'll get 1:3.
Hope this helped.