The correct answer is A. relatives.
Relatives are people who are related to you by blood or marriage. They can be your parents, siblings, aunts, uncles, cousins, grandparents, and so on. Friends are people who you have a close relationship with, but who are not related to you by blood or marriage. Children are people who you have given birth to or adopted. Acquaintances are people who you know, but who you are not close to.
In the sentence “I have been betrayed by my own flesh and blood,” the speaker is saying that someone who is related to them by blood has betrayed them. This could mean that someone in their family has lied to them, cheated on them, or done something else that has hurt them deeply.
It is important to remember that betrayal can come from anyone, regardless of their relationship to you. However, betrayal from a family member can be especially hurtful because it can feel like a betrayal of trust and loyalty. If you have been betrayed by a family member, it is important to reach out for support from friends, other family members, or a therapist.