Index number expressing the relative sizes of both coarse and fine aggregates, is called A. Proportioning of aggregates B. Fineness modulus C. Grading of aggregates D. None of these

Proportioning of aggregates
Fineness modulus
Grading of aggregates
None of these

The correct answer is C. Grading of aggregates.

Grading of aggregates is the process of determining the proportions of different sizes of aggregates that will be used in a concrete mix. The goal of grading is to create a mix that has the right amount of each size of aggregate to produce a concrete that is strong, durable, and workable.

The fineness modulus is a measure of the fineness of an aggregate. It is calculated by dividing the cumulative weight of the aggregate retained on a series of sieves by the total weight of the aggregate. The fineness modulus is used to classify aggregates into different groups.

Proportioning of aggregates is the process of determining the correct proportions of different types of aggregates to be used in a concrete mix. The goal of proportioning is to create a mix that has the right amount of each type of aggregate to produce a concrete that is strong, durable, and workable.

None of these is the correct answer.