Five good habits to keep our surroundings clean

1: When you eat/drink something, bring the dish/glass back to the sink

2: Put things back where you found them

3: If you see things on the floor that shouldn't be there, pick it up

Try to think of the last 2 yourself!

Explanation:

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.

the answers are a and c