Question: In which room is the Mars professor staying?
Explanation:
Denote the professors by their institution names.
From (j) : Mercury, Pluto, and Mars stay in 201, 203 ,205 or 202, 204, 206.
From (i) Mercury stays in an odd numbered room. Thus Mercury, Pluto, and Mars stay in 201, 203 and 205 respectively.
From (d) and (k), Neptune stays in 206.
From (g) Pluto published 12 journals and donated to 8 institutions.
From (e), Jupiter published 8 journals less than Pluto and donated to 10 more institutions. Therefore, Jupiter published 4 journals and donated to 18 institutions.
From(c) the professor from room 202 published 24 journals. Hence, he cannot be Jupiter. Therefore, Uranus stays in room 202 and Jupiter in 204.
From (d), Uranus and Neptune put together published 40 journals. So Neptune published 16 journals.
From (h), Neptune donated to 24 institutions.
From (i) Mars published 8 journals.
Mars stays in room number 205
Hence, option (c).