Meaning: The term 'amounts' refers to quantities or levels of something, in this case, nickel and other metals.

Wrong options:

• elements: The word 'elements' is a noun that refers to fundamental substances, but it does not convey the idea of quantity, making it unsuitable in this context.
• detected: The word 'detected' is a verb that indicates the action of discovering something, which does not fit as a noun in this sentence.
• which: The word 'which' is a relative pronoun used to introduce a clause, but it does not serve as a noun to indicate quantity.
• whom: The word 'whom' is a pronoun used to refer to people, which is irrelevant in this context as it does not relate to quantities of metals.
• filled: The word 'filled' is a past participle that implies something is occupied, which does not fit the context of discussing quantities.

Correct answer: which

Explanation: The word 'which' is a relative pronoun that introduces a clause providing additional information about the metals mentioned earlier. It fits grammatically and contextually, linking the metals to their abundance in the solar system.

Meaning: The term 'which' is used to refer to a specific group or items previously mentioned, in this case, the metals.

Wrong options:

• amounts: The word 'amounts' is a noun that does not function as a pronoun to introduce a clause, making it unsuitable here.
• detected: The word 'detected' is a verb that does not serve as a pronoun and cannot introduce a clause, thus it is incorrect in this context.
• whom: The word 'whom' is a pronoun used for people, which does not fit as it does not relate to the metals or their abundance.
• elements: The word 'elements' is a noun that does not function as a pronoun and cannot introduce a clause, making it inappropriate here.
• filled: The word 'filled' is a past participle that does not serve as a pronoun and cannot introduce a clause.

Correct answer: detected

Explanation: The word 'detected' is a past participle that fits grammatically as it describes the action of discovering the material in glass and sand. It aligns with the context of discussing what has been found in relation to Psyche.

Meaning: The term 'detected' refers to the act of discovering or identifying something, in this case, the material found in glass and sand.

Wrong options:

• amounts: The word 'amounts' is a noun that does not fit grammatically as it does not describe an action or state of being, making it unsuitable here.
• elements: The word 'elements' is a noun that refers to fundamental substances, which does not fit the context of describing an action related to discovery.
• which: The word 'which' is a relative pronoun that cannot function as a verb or describe an action, thus it is incorrect in this context.
• whom: The word 'whom' is a pronoun used for people, which is irrelevant in this context as it does not relate to the action of detecting.
• filled: The word 'filled' is a past participle that implies something is occupied, which does not fit the context of discussing detection.