Question

special type of protein that speeds up chemical reactions
sucrose
factors that affect enzyme activity
protein
enzyme

Explanation:

Enzymes are defined as special proteins that act as biological catalysts, speeding up chemical reactions in cells. Sucrose is a sugar (disaccharide), protein is a broad class of macromolecules (enzymes are a type of protein but the option "Protein" is too general here), and "Factors that affect Enzyme Activity" refers to things like temperature, pH, etc., not the enzyme itself. So the correct option is the one labeled "Enzyme".

Answer:

Enzyme (the red - colored option with text "Enzyme")