C. he may eventually spend a large amount of money on health care costs.
<span><span>The answer is Human papillomavirus (HPV).
</span><span>
Among the different sexually transmitted infections (STI), HPV is considered as the most common STI. It can be passed on through intercourse and other sexual activities with an infected person. It is known to cause cervical cancers. </span></span>
Each cycle<span> can be divided into </span>three phases<span> based on events in the ovary (ovarian </span>cycle<span>) or in the uterus (uterine </span>cycle<span>). The ovarian </span>cycle<span>consists of the follicular </span>phase<span>, ovulation, and luteal </span>phase<span> whereas the uterine </span>cycle<span> is divided into </span>menstruation<span>, proliferative </span>phase<span>, and secretory </span>phase<span>.</span>