A growing number of U.S. bike riders are attracted to electric bikes for convenience, health benefits and their fun factor. Although ebikes first appeared in the 90s, cheaper options and longer-lasting batteries are breathing new life into the concept.

        Established bike companies and startups are embracing ebikes to meet demand. About 34 million ebikes were sold worldwide last year, according to data from eCycleElectric Consultants. Most were sold in Europe and China, where the bikes already have exploded in popularity. Recently, the U.S. market has grown to 263,000 bikes, a 25% gain from the prior year.

        The industry is benefiting from improved batteries as suppliers over the years developed technology for laptops, smartphones and electric cars. In 2004, the price of batteries used on ebikes fell, spurring European sales.

        But lower cost options are emerging, too. This month, three U.S. bikeshare companies, Motivate, LimeBike and Spin, announced electric bicycles will be added to their fleets. New York-based Jump Bikes is already operating an electric bikeshare in Washington, D.C., and is launching in San Francisco Thursday. Rides cost $2 for 30 minutes.

        The system works like existing dockless bikeshare systems, where riders unlock bikes through a smartphone app. “This is the beginning of a long-term shift away from regular pedal (踏板) to electric bikes,” said Jump Bikes CEO Ryan Rzepecki. “When people first jump on an ebike, their face lights up. It’s exciting and joyful in a way that you don’t get from a regular bike.”

        Two years ago, CEO Chris Cocalis of Pivot Cycles, which sells high-end mountain bikes, found that U.S. bike shops weren’t interested in stocking ebikes. Some retailers warned Cocalis that they’d drop the brand if it came out with an electric bike.

        Now that sales are taking off, the vast majority of bike dealers are asking Cocalis when he’ll make an ebike available. “There’s tremendous opportunity to get a generation of people for whom suffering isn’t their thing,” Cocalis said. “Ebike riders get the enjoyable part of cycling without the massive suffering of climbing huge hills.”

解析：D。根据题干中的Chris Cocalis和a greater opportunity可定位至最后一段第二句。该句中克里斯•科卡利斯表示，这是个绝好的机会，来满足不想吃苦的这一代人的需求。骑电动自行车的人可以享受骑行的乐趣，而不用承受爬坡的吃力。由此可知，科卡利斯认为电动自行车因其能满足这一代人追求舒适骑行的需求而销售前景广阔，D项符合题意，其中的comfortable riding对应原文中的the enjoyable part of cycling，故D项为正确答案。

错项排除：原文中没有提到电动自行车价格是否进一步下调，排除A项。根据原文最后一段可知，人们关注的是骑行的舒适度而非自身健康，爬坡对公众来说是一种痛苦，并非是公众对爬山越来越感兴趣，故排除B和C项。