Answer:
The correct answer is SENTENCE 4, because it is the only sentence that has a gerund (-ing form) as a subject and a subject complement (important information about the subject, cannot be taken out) at the end of the sentence. Below you can find the structure of each sentence.
Explanation:
Sentence 1
Russel = Subject
really= Adverb
enjoys = Verb
baking = Object
SUBJECT + ADVERB + VERB + OBJECT
Sentence 2
He= Subject
makes= Verb
the most delicious plum tarts = Object
SUBJECT + VERB + OBJECT
Sentence 3
His tarts = Subject
always = Adverb of frequency
have = verb
a perfect flaky crust = object
SUBJECT + ADVERB + VERB + OBJECT
Sentence 4
Learning how to bake from a master chef in paris = Gerund (-ing form) as subject
is = verb
one of his dreams = subject complement (important information linked to the subject)
GERUND AS SUBJECT + VERB + SUBJECT COMPLEMENT
