What should be the very last function performed in the lab before you leave? a) Bid the instructor farewell
b) Make sure that your locker is secure
c) Wash your hands
d) Arrange a time with your lab partner for lunch

c) Wash your hands

Explanation:

A laboratory or most popularly called as lab is a place or facility which provides controlled conditions where some educational research, scientific studies, experiments, testings, can be performed. The place is equipped with sophisticated machines, test samples, hazardous chemicals, instruments  etc.

The university or college lab, there is a incharge of the lab called as the lab instructor who is responsible for all the belongings of the lab and the safety of the experimenter or the students.

After performing some experiments or testing with some chemicals, the last and the most important thing we need to do is to wash our hand with soap or hand wash. it is very important because we touch many test samples and hazardous chemical which might go inside our mouth or eyes accidentally, which might be harmful to us.

So, it is important to wash our hand at last before leaving the lab.

*tilts head* sounds more like a statement