Which sentence uses a demonstrative adjective to point out something near?

a.
that bird in the city park sings a lot.

b.
those sheep can be heard from miles away.

c.
these boots i’m wearing keep my feet dry.

Consider the title and souce of the following articles. which one is most likely to exhibit a bias? (a) how to roast beef," by the food editor of a magazine (b) americans experiencing greater fatigue than previous generations, " by a harvard researcher (c) "americans' worsening eyesight not related to computer screen usage," by the public relations director of a major computer manufacturer (d) "sharing the burden: a history of cooperation," by a college professor