Please answer the following question: Read the following article and select the best answer. Article: I appreciate how biking to work allows me to be outside for at least a small part of my day. I'm a senior program director. If I didn't bike to work, I'd spend my weekdays almost entirely indoors--underground tunnel. On the bike, I get trees, air and a great way to get to know city neighborhoods. Of course, I also get bad weather and city traffic. But it's worth the trade-off. The weather's not often bad, and rain and snow have their charms. I've been cycling to work since the late 1990s. I started when the city was doing some construction in the subways and rerouting passengers, which would have lengthened my trip considerably. I tried riding my sister- in- law's bike to work one day and liked it, so I bought my own. Even though I hadn't biked since I was a child, I got back into it right away. I bike during all four seasons. In summer, I wear shorts and a T- shirt and carry a messenger bag over my shoulder for my lunch and anything else I need. Once at the office, I change into business- casual clothes. In winter, I wear layers and a thin hat under my helmet. A cold winter day can be the best time to be on a bicycle. When the air is clear, free of oppressive summer haze, the city can look beautiful. Biking to work also _ during the workday itself. I have a rack on the back of my bike that accommodates panniers that allow me to pick up groceries. During work hours, a colleague will occasionally need to send or retrieve documents by messenger. If I have the time, I volunteer. Pedaling 30 blocks and back is a nice way to take a break from work--and to save the office a few bucks on messenger fees. I'm sure that some people thinking my mode of transportation might be afraid of Midtown traffic. I'm no hero; I don't want to get hurt riding to work. It just takes time getting used to it. There's a risk, but all travel has risks. They're worth it to me. Question: What made the author began to ride a bike to work? - The author bought his own bike. - His sister- in- law lent him a bike. - There were few bikes on the street then. - The subway construction in the city was under way.
A:
The subway construction in the city was under way.