Read the following context and choose the best option to answer the question.
Context: This is the 3rd dinner I have cooked for this couple and they said this is my best dish that they have tasted to date . The meals keep improving ... yippee ! Honestly it is all about working out what your friends like , and cooking something catered to their likes and dislikes .
Question: What may be the reason why they are always over at speaker 's house to eat ?
Options: 
- Because they ca n't afford food .
 - Because they invite themselves over .
 - Because the speaker 's cooking is the best they 've ever had .
 - Because they eat fast food too much .


Because the speaker 's cooking is the best they 've ever had .