Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Week | Date | Opponent | Result | TV Time |
| --- | --- | --- | --- | --- |
| 1.0 | September 7, 1998 | at Denver Broncos | L 27–21 | ABC 9:00pm |
| 2.0 | September 13, 1998 | Indianapolis Colts | W 29–6 | ESPN 8:15pm |
| 3.0 | September 20, 1998 | Tennessee Oilers | W 27–16 | CBS 1:00pm |
| 4.0 | Bye | Bye | Bye | Bye |
| 5.0 | October 4, 1998 | at New Orleans Saints | W 30–27 | CBS 1:00pm |
| 6.0 | October 11, 1998 | Kansas City Chiefs | W 40–10 | CBS 1:00pm |
| 7.0 | October 19, 1998 | New York Jets | L 24–14 | ABC 9:00pm |
| 8.0 | October 25, 1998 | at Miami Dolphins | L 12–9 | CBS 1:00pm |
| 9.0 | November 1, 1998 | at Indianapolis Colts | W 21–16 | CBS 1:00pm |
| 10.0 | November 8, 1998 | Atlanta Falcons | L 41–10 | FOX 1:00pm |
| 11.0 | November 15, 1998 | at Buffalo Bills | L 13–10 | CBS 1:00pm |
| 12.0 | November 23, 1998 | Miami Dolphins | W 26–23 | ABC 9:00pm |
| 13.0 | November 29, 1998 | Buffalo Bills | W 25–21 | CBS 4:15pm |
| 14.0 | December 6, 1998 | at Pittsburgh Steelers | W 23–9 | CBS 4:15pm |
| 15.0 | December 13, 1998 | at St. Louis Rams | L 32–18 | CBS 1:00pm |
| 16.0 | December 20, 1998 | San Francisco 49ers | W 24–21 | FOX 1:00pm |
| 17.0 | December 27, 1998 | at New York Jets | L 31–10 | CBS 1:00pm |
Question:
Which opponent was playing on December 20, 1998?
Answer:
San Francisco 49ers