Which of the following is a possible source of market failure as economists use the term?

[Si L]

Which of the following is a possible source of market failure as economists use
the term?
A) No single landlord has sufficient market power to influence the general
rental-level in the rental accommodation market
B) The private costs of providing rental accommodation equal the social costs
of providing such accommodation.
C) No single tenant has sufficient market power to influence the general
rental-level in the rental accommodation market.
D) The nature of advertising in the real estate market may at times be
misleading.

my answer is D but not sure, need some help~

[Anjaree]

The answer is D.A and C are the case of perfectly competitive market which will be efficient. B is a good case of externalities.It won't cause a market failure.Only D will create a market power and market failure.