Which statement gives an advantage for a single-celled organism

Single celled or unicellular organisms use simple processes such as diffusion and active transport to gain nutrients. iii) Unicellular organism requires less energy and makes use of simple process such as diffusion to perform gas exchange.

Explanation:

EX: Single celled or unicellular organisms use simple processes such as diffusion and active transport to gain nutrients. iii) Unicellular organism requires less energy and makes use of simple process such as diffusion to perform gas exchange

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.