The likelihood that individuals have of sharing in the opportunities and benefits of society is known as
a. life chances.
c. both a and b
b. life expectancy.
d. neither a nor b

c. a & b

In a market economy, it is the consumers that will decide how to allocate the productive resources a business uses. The allocation of products is determined by a concept that is known as supply and demand. When there is a demand for a certain product, then obviously the business has to supply that product. It is the job of the business to look out for signs of demand of a certain product and they have to know just how much of that product he should supply. 

A market index is a resulting value created from the combination of several stocks and other  investment vehicles presenting its total value against a base value at a certain period. It is used to show the whole stock market at the same time keeping track with the way the market changes overtime. The practice of tracking the value of the stock market over a period of time can be used to benchmark to make a credible comparison of stock returns.

It's most likely choice a, it makes the most sense in my opinion.