Cross-site request forgery, also known as one-click attack or session riding and abbreviated as CSRF or XSRF, is a type of malicious exploit of a website where unauthorized commands are transmitted from a user that the website trusts.

Example and characteristics
If an attacker is able to find a reproducible link that executes a specific action on the target page while the victim is being logged in there, he is able to embed such link on a page he controls and trick the victim into opening it. The attack carrier link may be placed in a location that the victim is likely to visit while logged into the target site (e.g. a discussion forum), sent in a HTML email body or attachment.

Incorrect Answers:

C: Clickjacking (User Interface redress attack, UI redress attack, UI redressing) is a malicious technique of tricking a Web user into clicking on something different from what the user perceives they are clicking on, thus potentially revealing confidential information or taking control of their computer while clicking on seemingly innocuous web pages. It is a browser security issue that is a vulnerability across a variety of browsers and platforms. A clickjack takes the form of embedded code or a script that can execute without the user’s knowledge, such as clicking on a button that appears to perform another function.
References: https://en.wikipedia.org/wiki/Cross-site_request_forgery