Answer:
irregular ovulation ( D )
Step-by-step explanation:
Irregular ovulation is not one of the common causes of infertility. , The quality of the eggs in women/ size of the eggs affect the fertility status in women and this quality is affected by declining hormone levels that occur with age. while in the case of irregular ovulation the woman will have to put in more effort to determine her most fertile time but it won't affect her ability to conceive in general.