The three choices they have likely offered you are:
Equity generally refers to being given shares in the company, which means you own part of the company and are eligible to vote on company matters.
This is relatively straightforward, in that you are given a "thing" (the shares) which may or may not increase in value, and that you can sell to somebody else when you want.
Stock Options are a contract that specifies you can buy shares at a later date, for a pre-specified price. This means you do not have to commit to the shares immediately, and can wait to see if their price does rise (at which point, you can exercise the option to buy the shares; at a lower price than they're currently worth).
The Stock Option itself has value and depending on the contract may be tradable by itself.
This is harder to parse, as reducing it to a single symbol doesn't convey particularly much information. However, one possible meaning is percentage profit share.
This means you receive some percentage of the company profits, in years where a profit was made, but have no controlling stake in the company.
Of course, with all of these things - the specifics will be very dependant on the specific offer they give you. I'd recommend speaking to them about this and not assuming anything. Especially given the last one "%" - which could mean any number of different agreements to different companies.