1、buffet: a meal at which people serve themselves from a table and then stand or sit somewhere else to eat 自助餐

2、takeaway
a、a restaurant that cooks and sells food that you take away and eat somewhere else 外卖餐馆
b、a meal that you buy at this type of restaurant 外卖的饭菜；外卖食物

3、in retrospect: thinking about a past event or situation, often with a different opinion of it from the one you had at the time 回顾

4、under-capitalised: (about a business) not having enough money (capital) to be able to operate normally, pay debts and grow 资金不足。

5、Instead, she studied accountancy after leaving university, and a steadyifunspectacular professional path seemed set.

这个句子里if的用法比较少见，参见朗文的解释：used when adding one criticism of a person or thing that you generally like

e.g: Lunch was a grand if rather noisy affair.

所以G选项的意思就是：然而，离开大学后她学的是会计，一个平淡无奇的职业道路似乎已经铺就。