When mixed with sugar and acid, forms a gel that is added to jellies, jams, sauces, and salad dressings to make those foods firm.
a. hemicelluloses
b. gums and mucilages
c. starch
d. pectin

When mixed with sugar and acid, pectin  forms a gel that is added to jellies, jams, sauces, and salad dressings to make those foods firm. Correct D Pectin is a naturally occurring starch found in fruits and vegetables. This high-molecular-weight carbohydrate polymer contributes to the cell structure.

it's 150 100% postive

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