The Survival of Pyrite Grains Transported in Streams Along with Other

question 26

Multiple Choice

The survival of pyrite grains transported in streams along with other Archean sediments shows us that bacteria-produced oxygen was

• A) very rapidly building in the early atmosphere.
• B) being taken out of the atmosphere by chemical sinks in early Earth.
• C) not yet forming and would require more time for evolution to change that fact.
• D) no match for the vast quantities of oxygen produced in other ways.

---

Definitions:

Held-to-maturity Securities

Debt securities that an investor intends to hold until a fixed maturity date.

Debt Securities

Financial instruments that represent a loan made by an investor to a borrower, typically including terms for interest payments and the return of principal at maturity.

Fixed Maturity

A term related to fixed-income investments indicating the set date when the principal amount of the investment is paid back to the investor.

Equity Securities

Financial instruments representing ownership interest in a company, such as stocks, which provide shareholders with claims on assets and earnings.