Read the Paragraph Below and Answer the Questions That Follow

Read the paragraph below and answer the questions that follow.
(1) The city of Bangalore, India, is a jarring mixture of new and old. (2) Bangalore has become a world center of the computer software industry, and companies like IBM, Dell, and Hewlett Packard have built dozens of gleaming new buildings. (3) In contrast, the rutted dirt roads are choked with oxcarts, and three-wheeled taxis belch black fumes. (4) Over breakfast each morning at the Taj Residency Hotel, Indian programmers chat with American engineers about the latest piece of computer code. (5) Yet sandal-clad women carry baskets of tools on their heads at a nearby construction site, and workers drag a huge pipe into place using only ropes. (6) Each night, teams of programmers send their work by satellite uplink to teams on the other side of the earth. (7) However, they must rely on diesel generators because power outages lasting two or three hours occur almost every day.
Which of the following sentences does NOT contain a transitional expression that indicates contrast or comparison?

A) Sentence 3
B) Sentence 4
C) Sentence 7