I just started off with my CCNA prep with CCNA ICND2 Official Certification guide. There's an answer to a question of the DIKTA section of chapter 2 that confuses me. It's quesion 10 and it goes like this:
Switch SW3 is receiving only two Hello BPDUs, both from the same root switch, received on the two interfaces listed as follows:
Port Status VLAN Duplex Speed Type
Fa0/13 conn. 3 a-half a-100 10/100
G0/1 conn. 1 a-full a-1000 1000B
SW3 has no STP-related configuration commands. The Hello received on Fa0/13 lists cost 10 and the Hello received on G0/1 list cost 20. Which of the following is true about STP on SW3?
a. SW3 will choose Fa0/13 as its root port.
b. SW3 will choose G0/1 as its root port.
c. SW3 Fa0/13 will become designated port
d. SW3 G0/1 will become designated port.
According to the book answer b is correct, as 24 is the lower cost of the two paths.
In my opinion answer a is also correct as the question says "SW3 has no STP-related configuration commands". This means switch SW3 uses spanning-tree mode pvst (default), ergo Fa0/13 is root port for VLAN3, G0/1 is root port for VLAN1. Anything wrong with my assumption? Appreciate any comments.