The basic version of the Construction Cost Model (COCOMO), which
proposes quantitative, life-cycle relationships, performs what function?

A.
Estimates software development effort and cost as a function of the
size of the software product in source instructions modified by
manpower buildup and productivity factors

B.
Estimates software development effort and cost as a function of the
size of the software product in source instructions modified by
hardware and input functions

C.
Estimates software development effort based on user function
categories

D.
Estimates software development effort and cost as a function of the
size of the software product in source instructions

Explanation:
The Basic COCOMO Model (B.W. Boehm, Software Engineering
Economics, Prentice-Hall, Englewood Cliffs, New Jersey, 1981)
proposes the following equations:

The number of man-months (MM) required to develop the
most common type of software product, in terms of the number
of thousands of delivered source instructions (KDSI) in the
software product
MM = 2.4 (KDSI)1.05
The development schedule (TDEV) in months
TDEV = 2.5(MM)0.38
In addition, Boehm has developed an intermediate COCOMO
Model that also takes into account hardware constraints, personnel
quality, use of modern tools, and other attributes and their aggregate
impact on overall project costs. A detailed COCOMO Model, by
Boehm, accounts for the effects of the additional factors used in the
intermediate model on the costs of individual project phases.