The correct option is B Malthusian theory
A Malthusian catastrophe (also known as Malthusian check) was a prediction of a forced return to subsistence-level conditions once population growth had outpaced agricultural production.
The altruism theory of voting is a model of voter behavior, which states that if citizens in a democracy have social preferences for the welfare of others, the extremely low probability of a single vote determining an election will be outweighed by the large cumulative benefits society will receive from the voters preferred policy being enacted, such that it is rational for an altruistic citizen, who receives utility from helping others, to vote.