Step 1: What the case is testing.
Riya is a new investor about to put her savings into the stock market, so the passage is checking whether you can connect specific lines in the case to the functions SEBI performs to keep such investors safe.
Step 2: First function, Regulatory Function.
SEBI frames rules for brokers, sub-brokers and other intermediaries, registers them, and can call for information or conduct inspections to keep the market orderly. The lines in the passage that talk about SEBI overseeing how trading is conducted and who can operate in the market point to this Regulatory Function.
Step 3: Second function, Protective Function.
SEBI also exists to shield ordinary investors like Riya from unfair practices such as price rigging, insider trading and misleading information, so the part of the passage describing Riya's concern for the safety of her money links to this Protective Function.
Step 4: Final answer.
The two functions of SEBI quoted from the case are the Regulatory Function, framing rules and registering intermediaries, and the Protective Function, safeguarding investors like Riya from malpractices in the market.