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:
| District | Incumbent | Party | First elected | Results | Candidates |
| --- | --- | --- | --- | --- | --- |
| California 7 | George Miller | Democratic | 1974.0 | Re-elected | George Miller (D) 77% Norman Reece (R) 23% |
| California 18 | Gary Condit | Democratic | 1989.0 | Re-elected | Gary Condit (D) 86.7% Linda Degroat (L) 13.2% |
| California 20 | Cal Dooley | Democratic | 1990.0 | Re-elected | Cal Dooley (D) 60.7% Cliff Unruh (R) 39.3% |
| California 21 | Bill Thomas | Republican | 1978.0 | Re-elected | Bill Thomas (R) 78.9% John Evans (Ref) 21% |
| California 23 | Elton Gallegly | Republican | 1986.0 | Re-elected | Elton Gallegly (R) 60% Daniel Gonzalez (D) 39.4% |
| California 25 | Howard McKeon | Republican | 1992.0 | Re-elected | Howard McKeon (R) 74.7% Bruce Acker (L) 25.3% |
| California 30 | Xavier Becerra | Democratic | 1992.0 | Re-elected | Xavier Becerra (D) 81.3% Patricia Parker (R) 18.8% |
| California 35 | Maxine Waters | Democratic | 1990.0 | Re-elected | Maxine Waters (D) 89.3% Gordon Mego (AI) 10.7% |
Question:
What district is bill thomas from?
Answer:
California 21