Final answer:
In societies where polygamy exists, it can be an alternative to monogamy. Fraternal polyandry can exist due to a shortage of women. Some societies have no incest taboo.
Step-by-step explanation:
Based on the information provided, the following statements are true:
- Statement b): In societies where polygamy exists, it is often found as an alternative to monogamy rather than the only type of marriage practiced.
- Statement c): Fraternal polyandry exists in some societies as a result of a shortage of women caused by female infanticide.
- Statement d): There are some societies that have no incest taboo whatsoever.
It is important to note that statement a) and statement e) were not supported by the information provided.