Exposure in this context refers to the opportunity for investment in the market sectors specified.
the act of investing in something:
exposure to sth Her clients wanted more exposure to the energy and real estate sectors.
However exposure in financial terms can also refer to risk:
the risk of losing money, for example through a loan or investment, or the amount of money that might be lost:
exposure to sth The bank had relatively little exposure to subprime mortgages, which are issued to people with weak credit histories.
If they do walk away from the deal their total exposure is around £40 million.
Or in marketing:
the amount of public attention that someone or something, especially an advertisement or product, receives:
The overall winner is guaranteed lots of media exposure.
get/gain exposure The product is being advertised to bloggers with the hope of getting more exposure.
All these examples come directly from http://dictionary.cambridge.org/dictionary/english/exposure