People who have been drinking tend to their ability to tolerate alcohol.
a. understand
b. underestimate
c. overestimate

People who have been drinking end to overestimate their ability t tolerate alcohol  - c.

Indeed, this surge of confidence whilst drinking alchool has been often observed by many people and has also no doubt lead to many interesting encounters because of this overestimation. 

Dis correct. the rest of the answers are definitely wrong.without the basic needs like food, shelter and love , one will remain trapped in trying to fulfil these needs first which means putting food on the table and struggling to pay bills. it is impossible to achieve self actualization when without the basic needs which is the base.