The scientific understanding of the composition of the universe has indeed evolved over time, primarily influenced by advancements in observational techniques and theoretical frameworks. However, it seems there may be a bit of a misunderstanding in the options you've provided. Here's a clarification regarding the changes in estimates of the universe's composition:
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The percentage of ordinary matter has decreased: Initially, scientists believed that ordinary (baryonic) matter made up a larger portion of the universe's total composition. However, as observations improved, particularly with the cosmic microwave background radiation and galaxy surveys, it became clear that ordinary matter constitutes only about 5% of the universe.
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The percentage of dark matter and dark energy has increased: Conversely, estimates for dark matter and dark energy have become more prominent. Initially, dark matter was not as well understood or quantified, but now it is estimated to make up about 27% of the universe's total mass-energy content, with dark energy accounting for roughly 68%.
So to summarize, the understanding has shifted drastically from an emphasis on ordinary matter being a predominant component of the universe to recognizing that the vast majority of the universe's composition is in the form of dark matter and dark energy, much of which remains unknown and is a subject of ongoing research.
If you need a choice made from the options you've given, it would be more aligned with the fact that the percentage of ordinary matter has decreased and the understanding of what constitutes unknown matter (dark matter and dark energy) has grown substantially since 1970.
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