[HK1-K10] While not directly stated, it may be inferred from the text that _________.

Read the passage below and choose the correct answer A, B, C or D

ELEKTRON TO ELECTRIC

The first discovery of electricity is over 2,600 years old. Does that surprise you? Of course, there were no lights, telephones, refrigerators, radios, motion pictures, or television sets that long ago. In fact, all of these modern conveniences are of such recent development that you might well wonder how electricity could be any older than Thomas Edison’s development of the first practical electric light bulb in 1879.

The word electricity comes from the Greek word meaning amber, which is elektron. The fossilized sap of a pine tree, amber looks much like a hard lump of honey. In 600 B.C., a Greek philosopher named Thales rubbed a piece of amber against his sleeve to shine it. Much to his interest, he found that the rubbed amber attracted small bits of lint, feathers, and dried leaves. This property of attraction was a strange characteristic which he thought only amber had. Today, our word electricity still goes back to Thales’ early discovery about amber.

More than two thousand years after Thales, an English physician discovered that other substances also had this characteristic of electricity. From then on, more and more men added to the knowledge of electricity. They set off the many developments and discoveries which have brought about our electrical era of today.

Câu hỏi:

While not directly stated, it may be inferred from the article that _________.

• 
  A.
  amber is the only substance that can be magnetized
• 
  B.
  electricity is a recent discovery
• 
  C.
  Thomas Edison really invented electricity
• 
  D.
  facts may be observed long before they are put to practical use