Leona purchased 1,200 shares of the Lakeview Mutual Fund at an offer price of $4.20 per
share. She later sold the shares at a net asset value of $4.95 per share. During the time
Leona owned the shares, Lakeview paid a dividend of $0.42 per share. What is her return
on investment?
A. 27.9% C. 10.7%
B. 17.9% D. 3.6%

I really need help with this question... don't know how to solve it

You need to be looking at what she actually put into the shares. i.e. her investment is anything she paid out. And then what she got back out of owning those shares. i.e. what was everything she got paid? In a way you can think of it just like you would revenues and expenses. You'd take everything you made, everything you spent, subtract the two and get net income. Same thing here. That's her "net" return.

Any time you have a return on something, or a rate on something, you divide the first something by the second something. i.e. return on investment is the return (what they got net) divided by investment (what they put in).

See what you can do with it.