What is a combined technique that transfers dna from gel electrophoresis to a membrane, then detects specific dna sequences?

The correct answer would be southern blotting.

Southern blotting is technique used in molecular biology to determine the presence of specific DNA sequence in DNA samples. It is named after the scientist Edwin Southern who first published it in 1975.

The steps involved in this technique are:

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.

condenser is used to focus in the light microscope.