Can 49ers receiving corps make the grade in 2017?

Daily 49ers blog for NBC Bay Area website: In 2016, San Francisco's wideout group was the worst in the NFL. After multiple changes, can it take a big step forward in 2017?http://www.nbcbayarea.com/news/local/Questions-Linger-Over-49ers-Revamped-Receiving-Corps-427468593.html