Which protects nerve endings at the ends of fingers and toes? joints
hair
nails
muscle

Nails

Nails protects nerve endings at the ends of fingers and toes Nails are the special thin, plates at the ends of fingers and toes of humans and some other animals. Nails are part of the accessory structures that constitute the integumentary system. Nails are made up of densely packed dead keratinocytes and are produced on the nail bed.

Explanation:

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms