單項選擇題The biggest mistake a workplace leader can make with office culture is failing to devise one at all. How do you know if your office culture is helping， or hurting， your employees， and as a result your bottom line？ Designing a thoughtful（周到的）office culture  is so important for a new company. Here are some aspects where a leader should be careful not to make mistakes. A cohesive （和諧一致的） office culture starts at the top and is built with intention. Face book’s founder projects a laid -back vibe （氛圍）. That sets the tone for his $200 billion company，  Where he visits weekly Q and A sessions from his staff， loads up the perks， and courts a young team that closely mirrors his target market， positioning Face book are especially designed for their wants and needs.  Strict dress code or early start time may seem like an easy way to build professionalism （職業(yè)化）in your workplace， but is there a good reason for it？ Strict requirements that work in a law office may erode the work ethic at a hip tech startup. Make sure to back up your rules with reason. For example， at Culture Studio， a T -shirt design and printing company， you’d better believe there’s no place for ties. Employees are  encouraged to dress down in their brand’s merchandise or their competitors’（  Leadership shouldn’t abandon culture development there. Good employees tend to be goal？oriented over-achievers， so put your budget on that with team -building activities， contests， and incentives for the best. Think critically about the ideal employees for your team， what makes the tick， and how you can support them， within and outside of their role in the company’s goals.  Setting the tone for your workplace starts with each hire and at every level in the company. At digital marketing firm Mabbly， every hiring decision is made with the company’ s vision in mind： a creative and young team of approachable （伸手可及的） guides that help clients to understand the seemingly mysterious world of PR public relations in this internet age.What is the main topic of this article？（） 

A.How to write business emails and memos.
B.How to design a thoughtful office culture.
C.How to set rules for employees to follow.