An international team of astronomers working at telescopes in the Cana

(A) astronomers working at telescopes in the Canary islands and Spain has detected at least 18 huge gas spheres estimated to have 5 to 15 times the mass of Jupiter


(B) astronomers working at telescopes in the Canary islands and Spain has detected at least 18 huge gas spheres estimated to be 5 to 15 times Jupiter's mass

1) Illogical comparison: "gas spheres estimated to be 5 to 15 times Jupiter's mass". This part says that gas spheres are 5 to 15 times the mass of Jupiter. "gas spheres" cannot be measurement: Let's say Jupiter weights 10000000 tons. According to answer choice (B), "gas spheres" are between 50000000 and 150000000 tons. Not so. Instead, (B) should say "gas spheres are 5 to 15 times as massive as Jupiter" or "gas spheres estimated to have 5 to 15 times the mass of Jupiter".

2) "Jupiter's mass, the solar system's largest planet": Here, the red part seems to modify "mass" of Jupiter. Illogical.


(C) astronomers is working at telescopes in the Canary islands and Spain, having detected at least 18 huge gas spheres that are estimated at 5 to 15 times the mass of Jupiter

1) Error of idiom: "estimated at 5 to 15 times". The correct idiom here should be "estimated to have 5 to 15 times"

2) when "having + V_ed" comes after the clause it modifies, you can almost always eliminate any answer choice that uses such structure. Yet, There are some (OA)s that use such structure. For example, https://gmatclub.com/forum/some-patient ... 83070.html

"having + V_ed" should be simultaneous with one action and prior another action. (C) does not have such time sequence.

(D) astronomers, working at telescopes in the Canary islands and Spain, and has detected at least 18 huge gas spheres estimated at 5 to 15 times the mass of Jupiter

1) Error of idiom: "estimated at 5 to 15 times". The correct idiom here should be "estimated to have 5 to 15 times"

2) If you omit the modifier between two commas, you get "astronomers and has detected". To be honest, I don't know how to call this error: error of run-on or error of parallelism. Maybe, Para-runon!

(E) astronomers, working at telescopes in the Canary islands and Spain, has detected at least 18 huge gas spheres they have estimated to be 5 to 15 times Jupiter's mass

1)"Jupiter's mass, the solar system's largest planet": Here, the red part seems to modify "mass" of Jupiter. Illogical.

2) subtle change in meaning: "comma + V_ing" must be concurrent with the main action in a clause. Here, the main action is "has detected", an action that took place in the past and has already stopped but has something to do with the present. So, since the main action in the clause is in the past, "working..." must also be in the past. Hence, (E) says that astronomers have already stopped working. If you are given more than one gramatically correct answers, just go with the original meaning as long as it is reasonable.

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