Which of the following statements is not true? Sexual fantasies allow people to experience sexual situations they may not be comfortable acting out. According to research, only 10% of college females have masturbated. Outercourse is a safe way for couple to engage in physical contact without risking pregnancy. Masturbation is a healthy and common expression of sexuality.

According to research, only 10% of college females have masturbated.

Explanation:

Sexual feeling is one of the strongest feeling that might occur in the organisms. The feeling of the sexual arousal is known as orgasm that induce the sex desire in the organisms.

Sexual fantasies helps the individual to experience the sexual desire and can be done by masturbation. The 10% female masturbate is not the correct statement as more than 10% females are involved in masturbation. The feeling might differs  from person to person.

Thus, the correct answer is option (2).

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added