Answer:
a. imagery from his nightmares
Step-by-step explanation:
At the beginning of Surrealism, the paintings only had to do with the madness of the failed act. A common exercise among artists was to write a sentence on paper, the first one that comes to mind. He moved to another, with the paper folded so that he would not see what was written. And at the end of the page, crazy ideas came up and were soon painted on the pictures. Dali went further. With a little help from chemicals (opium and absinthe are said to be quite popular with the artists living in Paris at the time), he entered his deepest fears and traumas that were stored in his memories, as in a dream. And with the teachings of Sigmund Freud, he understood how his paintings should be painted.