Which of the following activities would be a good example of congressional casework?

Which of the following activities would be a good example of congressional casework?
 
  a. analysis of an incumbent's policy positions prior to a debate
  b. analysis of police force effectiveness
  c. analysis of water quality within a district
  d. assistance to a constituent in obtaining a Social Security check

Question -2-

Which of the following is an example of grassroots/outside lobbying?
 
  a. an e-mail encouraging members to contact their senators and representatives in Congress
  b. an organization asking members for donations to support the group's work
  c. a meeting held with a legislator in the legislator's home district
  d. a group submitting written testimony in a congressional hearing