Karl marx took a quote from louis blanc that said, "from each according to ability, to each according to need". this philosophy was adopted by karl marx & friedrich engels as the motto for communism. what does this mean?

The phrase "From each according to ability, to each according to need" means that one should contribute to the work force according to his ability and accordingly take what he needs from the society. So this refers to the free access to and distribution of goods, services and capital. Though the slogan was given by August Becker and Louis Blanc, it was popularized by Marx.

answer; i do believe its (b) 12.5 years of age;