All deliveries—please report to Reception immediately upon arrival for authority to unload.Drivers should
speak to Reception after delivering goods.
unload vehicles at Reception.
call in at Reception before unloading.
阅读材料的意思是“所有的交货一旦到达，请立即报告给Reception，然后获取官方的许可卸货”。也即是说“司机在卸货之前要拜访Reception”，所以选C。