By the end of the year, according to Reuters, BYD should have 10 GWh of battery production capacity, which it expects to increase to 34 GWh by 2020 with a new factory in Brazil—about the same capacity as Tesla’s.Other Tesla rivals rushing to the battery production scene will be iPhone manufacturer Foxconn and LG Chem, which is already one of the top three battery makers.
In the context of the input sentence, determine the relationship between 'iPhone' and 'Foxconn'.
Options: legal form, location of formation, manufacturer, business division