Questions

You cannot see a microorganisms without using a Microscope. You also cannot taste or smell microorganisms such as bacteria in contaminated food.

Enzymes are protein macromolecules. Enzymes are almost always made of proteins only. Proteins are large biopolymer molecules that are made up of repeating monomer units called amino acids. There are 20 different common amino acids that make up proteins like enzymes. Of these, nine amino acids are essential, which means you must get them from your diet.

Enzymes catalyze chemical reactions in biological systems. This means that they speed up the rate of the reaction.

Relegate means Assigning an inferior rank or position to. That means, downgrading or pulling down, lower a person.

All other options have words with opposite in meaning.

Hence, Relegate is an English word which is similar in meaning to Downgrade.

An explicit intent explicitly defines the activity the developer wishes to start. 

Script code :

Intent myIntent = new Intent(this, MyNewActivity.class);

startActivity(myIntent);