As per the report released by the U.S. journal Science on 26 July 2018, on which planet was a massive underground lake detected?

1. A

   Jupiter

   Jupiter has icy moons with possible subsurface oceans, but the 26 July 2018 Science report keyed here was not a Jupiter underground lake. This option is not the key.

2. B

   Saturn

   Saturn’s moon Enceladus has a known subsurface ocean, but the July 2018 Science splash in this paper is Mars. This option is therefore wrong.

3. C

   Venus

   Venus is extremely hot at the surface; the reported massive underground lake was not Venus. This option is not the key.

4. D

   Mars

   In July 2018 Science reported radar evidence from Mars Express of a stable body of liquid water beneath the south polar ice of Mars. That is the massive underground lake of the stem. This option is the official key.

Summary. Official key is (d) Mars. The MARSIS radar on Mars Express suggested a subglacial lake at Ultimi Scopuli near the south pole. Jupiter, Saturn and Venus are other planets with different water stories. The dated US journal report matches Mars. Only (d) is keyed.