I’ll claim A and the title.
Title
第 is a prefix to form ordinal numbers. In this case, it precedes 3, so third.
話 is a counter for stories, so 3rd episode in this case.
75歳 is something we’ve seen before, the age of the patient Saitou’s in charge of and this is connected with the possessive 『の』.
値段【ねだん】is the cost.
So: Episode 3: the cost of 75 years (of age).
A
Saitou is sitting by his patient, lost in thoughts.
先生まだ残ってらしたんです『か』?
先生【せんせい】can be teacher or doctor;
まだ: yet, still;
Then comes 残る. 残る is a godan verb and it has the meaning of “to remain, to be left”. It is conjugated in the 〜て form.
Regarding the 〜て form:
It does not indicate tense by itself, however, it combines with other verb forms to create other tenses.
So that’s clear so far but we’re still missing information. Let’s keep reading:
Additionally, the ~ te form is used in Japanese to connect verbs in a sentence in order to list out successive actions. Used to connect two or more verbs, the ~ te form is used after all but the last sentence in a sequence. The following are examples of this particular ~te usage in a sentence.
So maybe here it is to represent a sequence of action since there’s no いる・います to indicate the progressive state. Sequence implies a minimum of two actions. I don’t know where the second action is, it could be in the next bubble perhaps.
です『か』at the very end is asking a question. The ん which precedes it is a colloquial version of \color{blue} {の} です if I recall correctly.
Questions
①Am I right about my interpretation of 残る?
②Am I right about my interpretation of んです?
③What is the purpose of 〔らした〕in the sentence?