Table: election_results_1991
Columns: constituency
winner
party
margin
runner_up_a
party_a

Question: Who is the constituency when the runner-up was d. Venugopal? 
SQL: SELECT "constituency" FROM election_results_1991 WHERE "runner_up_a" = 'D. Venugopal'

Question: What is the party where the constituency is 10. Tindivanam? 
SQL: SELECT "party" FROM election_results_1991 WHERE "constituency" = '10. Tindivanam'

Question: What is the party when the constituency is 1. Chennai North? 
SQL: SELECT "party" FROM election_results_1991 WHERE "constituency" = '1. Chennai North'

Question: How many margin results are listed in the election that was won by L. Adaikalaraj C and the party was the Indian national congress? 
SQL: SELECT COUNT("margin") FROM election_results_1991 WHERE "party" = 'Indian National Congress' AND "winner" = 'L. Adaikalaraj c'