Quasars---celestial objects so far away that their light

Question

Quasars---celestial objects so far away that their light takes at least 500 million years to reach Earth---have been seen since 1963. 
For anything that far away to appear from Earth the way quasars do, it would have to burn steadily at a rate that produces more light than 90 billion suns would produce.
But nothing that burns at a rate that produces that much light could exist for more than about 100 million years. 

If the statements above are true, which one of the following must also be true on the basis of them? 

A. Instruments in use before 1963 were not sensitive enough to permit quasars to be seen. 

B. Light from quasars first began reaching Earth in 1963. 

C. Anything that from Earth appears as bright as a quasar does must produce more light than would be produced by 90 billion suns. 

D. Nothing that is as far from Earth as quasars are can continue to exist for more than about 100 million years. 

E. No quasar that has ever been seen from Earth exists any longer.

OlegC · Answer

It is E

It follows from the passage that quasars cannot live longer than 100mill years. But as the light from a quasar takes 500mill years to reach Earth the conclusion is that this light reaches Earth AFTER the quasar that emitted it ceased to exist. So, if a quasar is seen from Earth then this quasar no longer exists - choice E

Karthik · Answer

E is definitely not right. The fact that quasars cannot be seen from earth does not mean that they cease to exist.

C sounds good..anyone else??

OlegC · Answer

You misread option E. E deals with quasars that ARE SEEN from Earth

C is bad. Moon appears from Earth much brighter than any quasar but it does not shine like billions of suns. The distances do matter

krish · Answer

E is my choice too. 

C provides information from only one premise while, E concludes the whole paragraph.

bigtooth81 · Answer

Nope. The ans should be D. Here is the logic

Presume that the light of a quasars seen from the Earth is the quasars's first light. The quasars can't last more than 100 millions years. Hence, the light of it can't be seen for any longer than 100 millions years. So D is the ans.

Please correct me if I'm wrong.

OlegC · Answer

Choice D says nothing about the distant obect. D doesn't say that this object is visible from Earth nor that it emits any light at all

bigtooth81 · Answer

Hey, there's something Pro.Stephan Hawking can help here. 

The distance and the time for the light of quasars to reach the Earth is nothing here. It takes 500 millions years for the light to reach the Earth. When the quasars dies, its light still on the way to the Earth and the light can be seen for at most 100 millions years.

OlegC · Answer

This logic supports choice E rather than D

bigtooth81 · Answer

Waaaawwwww, I misread D, it is clearly too extreme. Yeah, E is the correct ans. Thank you OlegC.

chunjuwu · Answer

thank you. 

the OA is (E)

Quasars---celestial objects so far away that their light

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