hello rashmi

let us understand this one in more details....

first and foremost this is a weaken CR type
we need to weaken the causal relationship that says comp use tends to reduce television viewing

if we can say that comp owners already belong to a group that have long been known to spend less time watching TV then the causal relation bet comp use and reduce in TV viewsing is weaken...this is becoz such comp owners are people who are know to have spend less time watching tv

so comp use tends to reduce tv view is weaken

now let us look at A..it has no bearing on the caual mechanism used in the arg....

HTH!