What element has good conductivity but is also brittle? I'm confused by what element(s) can be identified to have these properties.

The following is text from my 2019-2020 Kaplan MCAT General Chemistry book under the metalloids section


  Silicon (Si) has a metallic luster but is brittle and a poor conductor


So onto the MCAT Concept Check 2.2:


  Identify a few elements that  likely possess the following  properties
  
  
  Good conductivity but brittle
  


I flip to the answer key and it says:


  Metalloids exhibit brittleness but good conductivity


So I'm confused how this makes sense because Si was the main example they provided in that passage, and it seems to contrast the two points they make.

So what is an actual example of good conductivity but brittle??
Whether a "metalloid" is both brittle and a good conductor depends on what you mean by "metalloid", which varies in literature, what is a "good" level of (electrical) conductivity, and even what exactly you mean by "brittle" versus "ductile".  Silicon, for instance, is only a semiconductor, with much less electrical conductivity than metals, when pure.

Wikipedia identifies beryllium and magnesium as brittle metals, although the latter can be made ductile with minor alloying.  Zinc is called "slightly brittle".