One common fertility treatment for women is to take medications such as follicle-stimulating and luteinizing hormones to stimulate the ovaries. why does this treatment increase the probability of producing twins or triplets?

During this treatment the multiple unfertilized eggs can be released and fertilized.

Explanation:

These hormones, also known as gonadotropins, are made in the brain naturally but can also be manufactured and given as injection.

When these hormones are made and released naturally by the body, their effect on the body is the release of one ovum/unfertilized egg per month.

However, when these hormones are given as injections, they give a different command to the ovaries - which is produce more eggs in a bid to increase the fertility.

The effect that this has, is that the more the number of eggs produced, the higher the chances of multiple eggs being released by the ovaries and ending up fertilized. This then leads to the increased chances of twin or multiple pregnancies.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.