Its (a)
(i) Excretion is the ability to clear waste from the body. For example, humans excrete nitrogen when they urinate and carbon dioxide when they breathe out. Plants excrete oxygen through their leaves.
(ii) Irritability is sometimes called sensitivity.Sensitivity is the ability to notice and react to changes in the environment. When a mouse runs into its hole after seeing a hawk, it is showing sensitivity. Plants also show sensitivity when they grow toward the light.
(iii)All living organisms have the ability to produce young ones. Lower organisms reproduce asexually whereas the higher organisms reproduce.
I GUESS YOUR DOUBTS ARE CLEARED..
THUMBS UP..
