Answer:
a. exercise
it is associated with less or lack of physical activity.
Specificity is the answer. You are targeting a certain muscle in your body to improve it for an upcoming sport or activity like running a marathon or entering a Mr.Olympian body-building competition.
Head injury, as your head is your skull, damaging your skull is very serious as your brain is located there and damaging your brain could probably kill or limit some abilities
What is the difference between formal and informal language?
Formal and informal language serve different purposes. The tone, the choice of words and the way the words are put together vary between the two styles. Formal language is less personal than informal language. It is used when writing for professional or academic purposes like university assignments. Formal language does not use colloquialisms, contractions or first person pronouns such as ‘I’ or ‘We’.
Informal language is more casual and spontaneous.