What Is the Most Common Way in Which Sinkholes Form

question 17

Multiple Choice

What is the most common way in which sinkholes form?

• A) a small explosion of methane gas from coal beds
• B) a small explosion of CO₂ gas from dissolving limestone
• C) a rising dome of salt finally reaches the surface
• D) the roof of a cave collapses

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Definitions:

Estrogen

A group of hormones important for sexual and reproductive development, primarily in females.

Corpus Luteum

An ovarian structure that forms after ovulation from the ruptured follicle, responsible for the production of progesterone during the early stages of pregnancy.

Corpus Albicans

The corpus albicans is the regressed, fibrous remains of the corpus luteum in the ovary, following the absence of pregnancy.

Progesterone

A steroid hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species.